Compression Or Pressure Treatment Patents (Class 528/502C)
  • Patent number: 6166118
    Abstract: A process for emulsifying a functionalized polyolefin is described. A functionalized polyolefin having a weight average molecular weight greater than 10,000, a fatty acid, a base in an amount sufficient to neutralize the functionalized polyolefin and the fatty acid, a surfactant and water are mixed in a pressure reactor vessel to form a pre-emulsion concentrate having a solids concentrate ranging from about 55 to 90% by weight. The pre-emulsion concentrate is then heated with agitation in the reaction vessel to an emulsification temperature, preferably at or above the melting point of the highest melting polymer in the formulation, for a time sufficient to form an emulsion concentrate. Water is then added to the emulsion concentrate within the pressure reactor vessel, diluting the solids content to about 5 to 50% by weight, and heated with agitation to the emulsification temperature for a time sufficient to form a functionalized polyolefin emulsion. Preferably, the resulting emulsion is rapidly cooled.
    Type: Grant
    Filed: June 12, 1998
    Date of Patent: December 26, 2000
    Assignee: Eastman Chemical Company
    Inventors: Kenneth Wayne Hyche, Terry Lynn Cutshall, Wallace Neville Cox, Stephen Louis Poteat
  • Patent number: 6156872
    Abstract: The invention is related to non-linear, paraffin-soluble olefin/carbon monoxide and olefin/acetylene/carbon monoxide copolymers. The invention is also related to a method for preparing olefin/carbon monoxide copolymers by heating a feed of at least one olefin, carbon monoxide, carbon dioxide, hydrogen, and methane in the presence of a free radical polymerization initiator. More particularly, the feed comprises at least one olefin, the total olefin amount ranging from about 5 to about 40 mole %, carbon monoxide in an amount ranging from about 1 to about 40 mole %, hydrogen in an amount ranging from about 4 to about 55 mole %, carbon dioxide in an amount ranging from about 3 to about 10 mole %, and methane in an amount ranging from about 4 to about 85 mole %. The feed may also include acetylene in an amount ranging up to about mole %.
    Type: Grant
    Filed: January 19, 1999
    Date of Patent: December 5, 2000
    Assignee: Exxon Research and Engineering Co.
    Inventors: Abhimanyu O. Patil, Donald N. Schulz, Raymond A. Cook, Michael G. Matturro
  • Patent number: 6136951
    Abstract: A method for evaluating the polymer growth inhibition ability of a compound or compounds is disclosed wherein the method comprises:A) weighing a dry seed of insoluble polymer capable of growing via a living polymerization mechanism;B) subjecting the seed of insoluble polymer to conditions capable of causing a living polymer to grow via a living polymerization mechanism;C) drying the seed; andD) weighing the seed a second time to determine any increase in weight;wherein the polymer growth inhibition ability of the compound or compounds is inversely proportional to any increase found in weight of the seed.
    Type: Grant
    Filed: August 16, 1999
    Date of Patent: October 24, 2000
    Assignee: Uniroyal Chemical Company, Inc.
    Inventors: Brigitte Benage, Brendan J. Geelan, Gerald J. Abruscato
  • Patent number: 6096859
    Abstract: A process of controlling the molecular weight and dispersity of poly(p-ethylphenol) and poly(m-cresol) synthesized enzymatically by varying the composition of the reaction medium. Polymers with low dispersities and molecular weights from 1000 to 3000 are synthesized in reversed micelles and biphasic systems. In comparison, reactions in bulk solvents resulted in a narrow range of molecular weights (281 to 675 with poly(p-ethylphenol) in a DMF/water system and 1,400 to 25,000 with poly(m-cresol) in an ethanol/water system). Poly(p-ethylphenol) was functionalized at hydroxyl positions with palmitoyl, cinnamoyl, and biotin groups.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: August 1, 2000
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Joseph A. Akkara, David L. Kaplan, Madhu Ayyagari
  • Patent number: 6060527
    Abstract: A process for recovering the resin contained in optical information recording media having either a thin metal film layer or a printed coating film layer, coated on at least one side of a resin substrate,which comprises the following steps of:(1) rolling the recording media,(2) bringing the rolled recording media into contact with hot water,(3) separating the coating film peeled from the recording media,(4) grinding the resulting recording media,(5) bringing the obtained small pieces of the recording media into contact with hot water to detach the thin metal film component, and(6) separating the detached thin metal film component from the small pieces of the recording media to recover and obtain the small pieces of the recording media.With this process, the coating layer can be removed effectively from the optical information recording media and the resin component in the recording media can be selectively recovered advantageously in industry.
    Type: Grant
    Filed: October 15, 1998
    Date of Patent: May 9, 2000
    Assignee: Teijin Chemicals Ltd
    Inventors: Hiromasa Shinomiya, Hideki Nakahiro, Tomohiro Nakado
  • Patent number: 6060584
    Abstract: A novel process for the production of degraded polyolefin is described. The process involves introducing polyolefin into one end of a vented multi-screw extruder, in the substantial absence of free radical initiator and oxidizing agent, and removing degraded polyolefin from the opposite end of the extruder.
    Type: Grant
    Filed: May 13, 1998
    Date of Patent: May 9, 2000
    Assignee: Eastman Chemical Company
    Inventors: Brenda Linette Neely, James Houston Scott
  • Patent number: 6056901
    Abstract: A method which is capable of manufacturing regenerated synthetic resin products, particularly slide fastener parts of regenerated synthetic resin, with good quality by using as a raw material such waste synthetic resin materials as emanate from the production line of slide fasteners of synthetic resin or arise from waste plastic products.
    Type: Grant
    Filed: August 28, 1998
    Date of Patent: May 2, 2000
    Assignee: YKK Corporation
    Inventors: Tsutomu Hamatani, Kenshi Hamamori
  • Patent number: 6025459
    Abstract: A method of forming a polyamide from a corresponding nylon salt material comprises providing a reaction mixture comprising a nylon salt and carbon dioxide; and then condensing the nylon salt in the carbon dioxide to form a polyamide and water. A method of forming a polyamide comprises providing a reaction mixture containing at least one lactam monomer and carbon dioxide; and then polymerizing the lactam monomer in the carbon dioxide to form a polyamide.
    Type: Grant
    Filed: February 12, 1997
    Date of Patent: February 15, 2000
    Assignee: The University of North Carolina at Chapel Hill
    Inventors: Joseph DeSimone, Ramone Givens, Yizeng Ni
  • Patent number: 5990195
    Abstract: A dental resin material which is formed into a dental prosthesis by milling processing is disclosed, comprising an acrylic resin polymer containing from 20 to 70% by weight of an inorganic filler having a mean particle size of from 0.01 to 0.04 .mu.m in diameter. A process for producing a dental resin material is also disclosed, which comprises polymerizing for curing a mixture comprising a combination of from 20 to 70% by weight of an inorganic filler having a mean particle size of from 0.01 to 0.04 .mu.m in diameter, a methacrylate or acrylate monomer having at least one unsaturated double bond, and a heat polymerization initiator while elevating the pressure and heating under the conditions that the pressure is from 50 to 300 MPa and that the temperature is from 100 to 200.degree. C.
    Type: Grant
    Filed: May 8, 1998
    Date of Patent: November 23, 1999
    Assignee: GC Corporation
    Inventor: Akishi Arita
  • Patent number: 5981619
    Abstract: A high bending strength and high density material for osteosynthesis, which comprises a biodegradable and bioabsorbable crystalline thermoplastic polymer material, and a high strength implant material, comprising a composite material in which a bioceramics powder of from 0.2 to 50 .mu.m in particle size is dispersed in the polymer material, wherein crystals of the polymer material are pressure-oriented not in a uni-axial direction but basically in parallel with a plurality of reference axes; and a production method by pressure orientation, which comprises preparing in advance a biodegradable and bioabsorbable crystalline thermoplastic polymer material or a dispersed mixture of the polymer material and a bioceramics powder and melt-molding it into a pre-molded material which is then press-charged at a cold temperature into a cavity of a closed type forming mold, thereby obtaining an oriented molding.
    Type: Grant
    Filed: May 14, 1997
    Date of Patent: November 9, 1999
    Assignee: Takiron Co., Ltd.
    Inventors: Yasuo Shikinami, Masaki Okuno
  • Patent number: 5955569
    Abstract: An improved method for increasing the relative viscosity and molecular weight of a polyamide polymer (such as nylon 6,6, nylon 6, and the like) while in the solid state involving the use of a phosphorus-containing catalyst (such as 2(2'-pyridyl) ethyl phosphonic acid or the like) in combination with an oxygen free gas characterized by a low dew point (typically below 30.degree. C. and preferably below -30.degree. C.). The combination of affording commercial operation at greater through put at lower temperature. Such a process is of particular value during the production of terpolyamide and multipolyamide polymer intended for use in colored nylon fiber manufacture.
    Type: Grant
    Filed: November 27, 1996
    Date of Patent: September 21, 1999
    Assignee: E.I. du Pont de Nemours and Company
    Inventors: Ramdas Dujari, Gregory D. Cramer, David Neil Marks
  • Patent number: 5948447
    Abstract: A method and apparatus for product recovery of polyolefins, particularly high molecular weight amorphous poly alphaolefins, wherein the use of water during the method is significantly decreased and wherein the intermediate stage of storing and drying the chunk form of the polyolefin is eliminated. Polyolefins produced in a reactor are heated and mixed by sigma blades in a kneader-extruder to remove any unreacted monomer(s). The polyolefin material in a liquid form is then transferred directly to an extruder to further remove any unreacted monomer(s) and catalyst(s). The invention further includes a method of measuring the inventory in a vessel using a gas of known quantity and known thermodynamic properties.
    Type: Grant
    Filed: April 10, 1996
    Date of Patent: September 7, 1999
    Assignee: Huntsman Polymers Corporation
    Inventors: Stephen C. McHaney, Steven L. Oetting, Karl L. Herzog
  • Patent number: 5917011
    Abstract: Impurities dissolved in a solid polymer and/or trapped in the spacial volume of the polymer can be removed quickly and efficiently in one or more relatively short pressurization/depressurization cycles, using a penetrant fluid (e.g. carbon dioxide) having at least some solubility in the polymer. Polymers with inherently slow or delayed elastic recovery at the temperature or temperatures at which the cycle is carried out (e.g. within the range of 20 to 200.degree. C.) or polymers with a high T.sub.g are the ones most efficiently treated. The penetrant is used to expand the polymer matrix, increasing its spacial volume. The pressure is then decreased rapidly, so that the impurities will migrate out of the polymer matrix before the matrix has a chance to relax or return to substantially its original volume. Each complete cycle should last seconds or minutes rather than hours.
    Type: Grant
    Filed: November 7, 1997
    Date of Patent: June 29, 1999
    Assignee: The Penn State Research Foundation University Park
    Inventors: John L. Duda, Sacide Alsoy
  • Patent number: 5908914
    Abstract: This invention relates to benzylic ether phenolic resole resins prepared in a sealed reaction vessel and their uses. The benzylic ether phenolic resole resins are prepared by heating phenol and an aldehyde in a sealed reaction vessel in the presence of a divalent metal catalyst without removing water generated by the reaction until an appropriate endpoint for the resin is reached. The benzylic ether phenolic resole resins produced by the process are preferably free or essentially free of unreacted formaldehyde and can be used in the resin component of phenolic-urethane foundry binders to make foundry cores and/or molds by the cold-box and no-bake processes. The cores and/or molds are used for making metal castings.
    Type: Grant
    Filed: July 17, 1996
    Date of Patent: June 1, 1999
    Assignee: Ashland Inc.
    Inventors: Thomas Edward Dando, William Rexford Dunnavant, Robert Bernard Fechter, Heimo Josef Langer
  • Patent number: 5861474
    Abstract: A process has been invented for removing contaminants (including solvent) from a flowing polymer, the process, in one aspect, including dissolving a sparingly soluble stripping agent into a flowing polymer, the sparingly soluble stripping agent stripping contaminants from the flowing polymer creating a mixture of contaminants and sparingly soluble stripping agent, which flows out from the flowing polymer, and separating the mixture from the polymer. In one aspect, recyclable sparingly soluble stripping agent is recovered and re-used.
    Type: Grant
    Filed: July 23, 1996
    Date of Patent: January 19, 1999
    Assignee: The Dow Chemical Company
    Inventors: Joseph P. Weller, Lawrence D. Wilson, Michele L. Rosenau, Pat Jimenez, Bernard M. Lescure
  • Patent number: 5854336
    Abstract: A process is provided for preparing a silicone elastomer composition for cosmetic products which includes the steps of feeding the silicone elastomer composition comprising a silicone rubber in a carrier fluid into a reactor, mixing the composition in the reactor, delivering the composition from the reactor into a high pressure pump, pumping the fluid into a device for reducing particles of rubber into smaller sizes and recirculating the resultant size reduced particles back to the reactor. The device for reducing particle size is preferably a high pressure fed homogenizer, most advantageously a sonolator.
    Type: Grant
    Filed: March 20, 1997
    Date of Patent: December 29, 1998
    Assignee: Chesebrough-Pond's USA Co., Division of Conopco, Inc.
    Inventors: Peter Anthony Divone, Sr., Brian John Dobkowski, Michael Charles Cheney, Salvador Pliego, Walter Anthony Biercevicz, Kenneth Paul Manzari
  • Patent number: 5814266
    Abstract: A method for improving consolidation of powder resin is provided. The method broadly includes the steps of: (1) sorting particles of the powder resin according to their diameter; (2) combining the sorted particles having a first diameter D1 with the sorted particles having a second diameter D2 so as to form a particle mixture; (3) applying a vibration to the particle mixture; (4) heating the particle mixture; and (5) delivering the particle mixture through a nozzle or into a mold. The particle diameters D1 and D2 are chosen so that once combined there is optimal close packing of the three-dimensional spaces between the powder resin particles.
    Type: Grant
    Filed: May 20, 1996
    Date of Patent: September 29, 1998
    Assignee: University of Kentucky Research Foundation
    Inventors: David A. Pienkowski, Eric A. Grulke, Robert J. Jacob
  • Patent number: 5807976
    Abstract: A method for product recovery method of polyolefins, particularly high-molecular-weight amorphous poly alpha-olefins, wherein the use of water during the method is significantly decreased and wherein the intermediate stage of storing and drying the chunk form of the polyolefin is eliminated. Polyolefins produced in a reactor are heated in a kneader to remove any unreacted monomer(s). The polyolefin material in a liquid form is then transferred directly to an extruder to further remove any unreacted monomer(s) and catalyst(s). Finally, the polyolefin material is pelletized using a pelletizer.
    Type: Grant
    Filed: February 9, 1996
    Date of Patent: September 15, 1998
    Inventor: Stephen McHaney
  • Patent number: 5804676
    Abstract: A process for continuously preparing a high quality methacrylic polymer with a high productivity is provided. The process comprises continuously polymerizing methyl methacrylate alone or a monomer mixture of methyl methacrylate and an alkyl acrylate by a solution polymerization using methanol as a solvent, directly feeding the resulting polymerization reaction product to an extruder having a plurality of vents, and extruding the polymer, while volatiles are removed through the vents.
    Type: Grant
    Filed: August 28, 1996
    Date of Patent: September 8, 1998
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Shinichi Hieda, Masahiro Kurokawa, Yasushi Higuchi, Shojiro Kawahara
  • Patent number: 5783137
    Abstract: The invention relates to a process and an arrangement for the three-dimensional forming of a fabric. The process comprises the steps of providing a countermold; preparing a complex sheet by superimposing a sheet of plastics, hot-melt material and a fabric; die-cutting the complex sheet; superimposing the die cut complex sheet over the fabric; attachment of the die cut complex sheet to the fabric by pressing and heating until the fabric is impregnated by melting of the hot-melt material; and application of the ensemble of the complex sheet and fabric to the countermold by blowing pressurized air. The arrangement comprises a frame receiving the fabric to be formed and which is movable through various workstations wherein the process steps take place.
    Type: Grant
    Filed: November 16, 1995
    Date of Patent: July 21, 1998
    Inventor: Miguel Alives Porta
  • Patent number: 5756659
    Abstract: A method of improving the oxidative thermal stability of ethylene polymers is disclosed. The method comprises removing residual unreacted monomer(s), solvent and thermally unstable species from the molten polymer. The resulting polymer is characterized by having an oxidative exotherm of not more than about 50 percent of the original polymer, as measured by differential scanning calorimetry.
    Type: Grant
    Filed: October 21, 1994
    Date of Patent: May 26, 1998
    Assignee: The Dow Chemical Company
    Inventors: Morgan M. Hughes, Michael E. Rowland, Chad A. Strait
  • Patent number: 5739266
    Abstract: The present invention relates to a process for modifying a polyethylene in an extruder by bringing the polyethylene into contact with oxygen or a gas mixture containing oxygen in the extruder, optionally in the presence of a relatively small quantity or preferably in the absence of short-term antioxidant agent. The polyethylene is then treated thermomechanically in the molten state in the extruder supplying a relatively high specific mechanical energy, the thermomechanical treatment is completed when the value of the loss tangent of the polyethylene characterizing its viscoelastic state decreases in a desired proportion. The polymer thus treated is particularly suitable for being transformed by blown extrusion into a film having a considerably increased bubble stability.
    Type: Grant
    Filed: August 16, 1995
    Date of Patent: April 14, 1998
    Assignee: BP Chemicals Limited
    Inventor: Alain Piana
  • Patent number: 5723518
    Abstract: A method is described for the preparation of aqueous coating compositions based on resin binders containing isocyanate-reactive hydrogen atoms and polyisocyanates, by mixing the components with water, wherein the mixture is forced at a pressure of from 1 to 30 MPa through a nozzle of small size in at least one dimension.
    Type: Grant
    Filed: January 6, 1997
    Date of Patent: March 3, 1998
    Assignee: Bayer Aktiengesellschaft
    Inventors: Lothar Kahl, Bernd Klinksiek, Dieter Schleenstein, Manfred Bock, Nusret Yuva
  • Patent number: 5698666
    Abstract: A process for finishing latex to form a dry resin and the resulting product. The process includes coagulating a latex of a thermoplastic polymer at a temperature at or just above the agglomeration temperature of the resin, dewatering the resin slurry to form a resin cake, drying the resin cake using extrusion technology to form a resin melt and solidifying the resin melt to form the resin. Preferred processes of the invention also include finishing the resin, such as by pelletizing and/or grinding it. More preferred processes of the invention include collecting and neutralizing the aqueous liquid byproducts from the dewatering and drying steps of the process. One embodiment of the invention includes utilizing water to solidify the resin melt, pelletizing the resin and drying the pellets.
    Type: Grant
    Filed: June 13, 1996
    Date of Patent: December 16, 1997
    Assignee: The Goodyear Tire & Rubber Company
    Inventors: Gary Lee Burroway, Lance Walter Lewis, John Charles Ullemeyer, Robert Donald Mate
  • Patent number: 5684124
    Abstract: Novel ultrahigh molecular weight linear polyethylene (UHMWLPE) in the form of a shaped article, exhibiting a unique combination of properties making the material useful as a bearing surface, in general, but particularly useful as a prosthetic hip joint cup and as other prosthetic shapes for replacement of other joints of the human body. A novel process for preparing this article is also disclosed.
    Type: Grant
    Filed: April 5, 1995
    Date of Patent: November 4, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Edward George Howard, Jr., Allan R. Champion
  • Patent number: 5672679
    Abstract: In a process for producing an amorphous thermoplastic resin composition comprising melt-kneading at least one amorphous thermoplastic resin, an improvement comprising melt-kneading the amorphous thermoplastic resin in the presence of not less than 1% by weight, based on the amorphous thermoplastic resin, of an organic solvent in a kneader having a vent hole(s) while maintaining at least one vent hole of the kneader under reduced pressure by means of an evacuator to remove the organic solvent so as to reduce the organic solvent content in the final composition to less than 1% by weight. Thermal deterioration of the resin during melt-kneading can be inhibited to provide a resin composition having well-balanced impact resistance and heat resistance and excellent hue.
    Type: Grant
    Filed: December 1, 1995
    Date of Patent: September 30, 1997
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Kiyoji Takagi, Koji Nishida, Megumi Kojima
  • Patent number: 5631346
    Abstract: Polyolefins are thermomechanically degraded in a twin-screw extruder without a downstream degradation apparatus, at from 300.degree. to 550.degree. C. and from 1 to 100 bar and in average residence times of the reaction mixture of from 0.5 to 10 minutes, by a process in which the pressure in the twin-screw extruder is changed periodically or aperiodically with a fluctuation of from 0.5 to 30 bar. The novel process is particularly suitable for the degradation of polypropylene.
    Type: Grant
    Filed: October 19, 1995
    Date of Patent: May 20, 1997
    Assignee: BASF Aktiengesellschaft
    Inventors: Andreas Deckers, Albin Berger, J urgen Hofmann, Roger Klimesch, Karl-Peter Farwerck, Hilmar Ohlig
  • Patent number: 5621070
    Abstract: Process for preparing an ultrahigh molecular weight linear polyethylene (UHMWLPE) by heating the material to above 280.degree. C. at atmospheric pressure in an inert environment. The treated polymer is then gradually cooled in this same atmosphere.
    Type: Grant
    Filed: December 5, 1995
    Date of Patent: April 15, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Edward G. Howard, Jr.
  • Patent number: 5576415
    Abstract: There are disclosed a method for drying and a method for solid-phase polymerizing a crystallizable polyamide being in an amorphous state which comprises regulating the moisture concentration in the polyamide at its glass transition temperature to at least 0.15% by weight as determined by Karl Fisher titration; heating the polyamide thus regulated at a pressure of at least one arm without reducing the moisture to crystallize the same up to a crystallinity of at least 15% and; further heating the polyamide thus crystallized at a temperature lower than its melting point under reduced pressure with a batchwise heating apparatus.
    Type: Grant
    Filed: August 7, 1995
    Date of Patent: November 19, 1996
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventor: Kazumi Tanaka
  • Patent number: 5567355
    Abstract: An intrinsically conductive polymer is in the form of a dispersible solid of primary particles with a specific surface area according to BET of >15 m.sup.2 /g and with an average diameter of less than 500 nm, in which preferably not more than 20% of aggregates with an average size >1 .mu.m are present in the particle size range >500 nm. For the manufacture of the polymer the polymerization is carried out in a solvent in which the appropriate monomer is soluble or colloidally dispersible, but in which the polymer that is formed is insoluble, whereby the temperature of the reaction mixture is not allowed to rise more than 5.degree. C. above the starting temperature.
    Type: Grant
    Filed: May 12, 1993
    Date of Patent: October 22, 1996
    Assignee: Zipperling Kessler & Co. (GmbH & Co.)
    Inventors: Bernhard Wessling, Harald Volk, Susanne Bl attner
  • Patent number: 5567802
    Abstract: Polycarbonate compositions are redistributed by melt equilibration using as the redistribution catalyst a tetraorganophosphonium hydroxide, preferably a tetra-(C.sub.1-6 alkyl)phosphonium hydroxide. Such catalysts have numerous advantages including greater redistribution efficiency, decreased color in the redistributed product and the capability of employment in the anhydrous state.
    Type: Grant
    Filed: November 20, 1995
    Date of Patent: October 22, 1996
    Assignee: General Electric Company
    Inventor: Patrick J. McCloskey
  • Patent number: 5545364
    Abstract: A polyester film having excellent heat resistance and insulation property is produced by the inventive process which comprises: melt-extruding a polyester resin into a sheet, extending the sheet to shape it into a film and treating the film thermally to heat-set, wherein the polyester resin has an intrinsic viscosity of 0.7 to 0.75 dl/g and other portions which satisfy formula (1) and the thermal treatment is carried out so that formula (2) is satisfied:[COOH]/[IV]<50 (1)1.0<S/D<1.2 (2)wherein:[COOH] represents the content (meq/10.sup.6) of terminal carboxyl groups in the polyester resin;[IV] represents the intrinsic viscosity (dl/g) of the polyester resin;S represents the X-ray crystal size (.ANG.) of the heat-set polyester film; andD represents the degree of crystallinity (%) of the heat-set polyester film.
    Type: Grant
    Filed: October 4, 1995
    Date of Patent: August 13, 1996
    Assignee: SKC, Limited
    Inventors: Il-Cheon Song, Sang-Il Kim, Young-Jin Lee
  • Patent number: 5543495
    Abstract: This invention concerns a process for increasing the molecular weight and viscosity of polyamides and other condensation polymers, by first injecting an inert gas into the polymer melt at elevated pressure, then stripping the volatiles from the polymer through the application of reduced pressure, followed by holding the polymer at elevated temperatures long enough for the reaction to occur. Activators may be added to the polymer. Port areas used in the stripping zone, may be kept hot for continuous operation.
    Type: Grant
    Filed: March 8, 1994
    Date of Patent: August 6, 1996
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Colin Anolick, Gregory D. Cramer, Ramdas Dujari, Win-Chung Lee, Sundar M. Rao, Robert C. Wheland
  • Patent number: 5532335
    Abstract: A method for thermally processing polyester pellets by crystallization and polymerization in the solid state which comprises providing a confined processing unit. The pellets are introduced to said unit along with a liquid medium. The combination of pellets and liquid medium is agitated to achieve mixing and the temperature of the agitated mixture is controlled to achieve treating of the polyester pellets in the agitated heating liquid medium at a temperature slightly below the sticking temperature of the polyester. The treatment is continued for a period sufficient to substantially increase the crystallinity and molecular weight of the polyester.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: July 2, 1996
    Assignee: Hosokawa Bepex Corporation
    Inventors: Gregory J. Kimball, Ilya Pikus
  • Patent number: 5521252
    Abstract: Acrylic multilayer polymer powders containing coagulated powders of emulsified latexes of acrylic multilayer polymers, which are suitable for drying methods using pressure dehydration extruders, etc, comprises not more than 40 wt % of a fine powder of a particle size of 212 .mu.m or less after drying, and have a volume of gaps of a pore size of 5 .mu.m or less after drying of not more than 0.7 cc per unit weight as measured by a mercurial pressure method. A desired monomer is subjected to emulsion polymerization to produce an emulsified latex of an acrylic multilayer polymer, which is then poured into a coagulating solution for coagulation.
    Type: Grant
    Filed: February 17, 1995
    Date of Patent: May 28, 1996
    Assignee: Mitsubishi Rayon Company Ltd.
    Inventors: Kaoru Matsuda, Hirofumi Uno, Akihiro Toritani, Jun Nakauchi
  • Patent number: 5478906
    Abstract: Novel ultrahigh molecular weight linear polyethylene (UHMWLPE) in the form of a shaped article, exhibiting a unique combination of properties making the material useful as a bearing surface, in general, but particularly useful as a prosthetic hip joint cup and as other prosthetic shapes for replacement of other joints of the human body, A novel process for preparing this article is also disclosed.
    Type: Grant
    Filed: May 18, 1994
    Date of Patent: December 26, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Edward G. Howard, Jr.
  • Patent number: 5463021
    Abstract: The aqueous dispersions from the polymerization of fluorinated thermoplastics can be worked up to a high value product (e.g., substantially purified of cations resulting from the polymerization) in a continuous manner, if the cations are first removed from the aqueous dispersion, the dispersion is then compressed and decompressed through small openings, thereby being coagulated, the coagulated phase is washed on a filter and partially dewatered, subsequently broken up to give a free-flowing product and this is dried to the desired residual moisture content. Qualitatively high value products, which can be directly fed to a melt extruder, are thus obtained with high throughputs.
    Type: Grant
    Filed: October 6, 1993
    Date of Patent: October 31, 1995
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gerhard Beyer, Reinhard Sulzbach, Eduard Wess, Rolf Hengel
  • Patent number: 5439719
    Abstract: A high-molecular-weight polyester is to be prepared in such a way that it is possible to very quickly and advantageously obtain even relatively small amounts having a very high molecular weight.This is achieved by preparing a polyester containing proportions of an alkene diol by continuing the polycondensation step until a viscosity number from 5 to 150 cm.sup.3 /g is reached and subsequently subjecting the polyester thus obtained to a treatment with ionizing radiation until the required viscosity number is reached.With the aid of the process of the invention it is possible to obtain high-molecular-weight polyesters having the desired property profile.
    Type: Grant
    Filed: August 24, 1994
    Date of Patent: August 8, 1995
    Assignee: GAF-Huels Chemie GmbH
    Inventors: Thomas Grosse-Puppendahl, Walter K. Homann
  • Patent number: 5434221
    Abstract: A process is provided for producing a low molecular weight isoolefin polymer by contacting at conversion conditions a higher molecular weight saturated isoolefin polymer, for example, polyisobutylene or a copolymer of a C.sub.4 to C.sub.7 isoolefin and a para-alkylstyrene, in the melt phase, with an initiator, such as an oxygen-containing gas, an organic peroxide or an azo compound.
    Type: Grant
    Filed: August 9, 1993
    Date of Patent: July 18, 1995
    Assignee: Exxon Chemical Patents Inc.
    Inventors: Donald A. White, Lawrence W. Flatley, Richard C. Yeh, Raymond F. Murphy